Doctor blade clearer



p 1967 A. c. MORROW ETAL 3,340,577

DOCTOR BLADE CLEARER Filed April 20, 1964 ENTORS HAR S. BARR. JR. ALFRED C. MORROW BY ATTORNEY.

United States Patent 3,340,577 DOCTOR BLADE CLEARER Alfred C. Morrow, Lowell, and Harry S. Barr, Jr., Charlotte, N.C., assignors to Pneumafil Corporation, Charlotte, N.C., a corporation of Delaware Filed Apr. 20, 1964, Ser. No. 360,978 Claims. (Cl. 19-98) This invention relates to the art of clearing textile fabricating equipment of undesired foreign matter, more particularly to the clearing of undesired accumulations of foreign matter from a doctor blade normally employed to implement the maintenance of textile processing rolls in a desired clean condition.

A variety of situations exist in which the maintenance of a desired surface condition on a moving surface is obtained by the utilization of a so-called doctor blade, in which a leading free edge of the blade abuts against the moving surface to displace any undesired foreign matter from the surface, and aids in maintaining desired conditions of surface smoothness on the moving surface. Where such doctor blades are used in connection with textile processing rolls, it is often found that notwithstanding the clearing effect of a doctor blade on the moving surface of the roll, the matter removed from the roll surface by the doctor blade tends to accumulate at the point of removal, and the accumulated matter often drops into the processed textile material to deleteriously effect the quality or processing thereof.

It is with the above problems and desiderata in mind, that the present means, including both method and apparatus, have been evolved. The novel means serve to positively displace any foreign matter collecting on the surface to be cleared, and/ or on the doctor 'blade, and direct this displaced foreign matter to a point remote from the line of movement of the material being processed.

It is accordingly among the primary objects of this invention to provide improved means for clearing foreign matter from a moving surface.

Another object of the invention is to provide means for positively displacing any foreign matter removed from a moving surface, and to implement'the feeding of the dis placed foreign matter to a point remote from the path of travel of any material being processed by the aid of the moving surface.

A further important object of the invention is to provide improved means for removing any foreign matter from a doctor blade clearer.

These and other objects of the invention which will become hereafter apparent are achieved by arranging an elongate flexible walled tube in proximity to the surface to be cleared. The tube is supported in a fashion permitting free rotation of the tube, with the side walls thereof in contact with the surface to be cleared, and with the motion of the surface to be cleared effecting rotation of the tube as a result of frictional contact between the tube and the surface to be cleared. A flap is extended, preferably tangentially from the surface of the tube, with the flap periodically displacing the tube from the surface to be cleared, and abutting this surface to positively displace any accumulations of foreign matter therefrom. A suction tube of the Pneumafil type is positioned adjacent the surface to be cleared, with orifices in the tube oriented to receive any foreign matter displaced by the motion of the tube with respect to the surface to be cleared.

A feature of the invention resides in the mounting of a tube support on a bracket which may be adjustably 3,346,577 Patented Sept. 12, 1967 tion of the flap of a flexible material, which in flexing against the surface to be cleared, and having the tensions in this flexed flap relieved as a result of passage from the cleared surface, acts to positively eject any foreign matter from the cleared surface.

A further feature of the invention resides in the formation of the support bracket with a clearer tube engaging flange which serves the twofold function of slowing down clearer tube rotation and aids in maintaining the clearer tube in a desired clean condition.

The specific details of a preferred embodiment of the invention, and their mode of functioning will be made most manifest, and particularly pointed out in a clear, concise, and exact terms in conjunction with the accompanying drawings wherein:

FIG. 1 is a perspective view in partial section, and with parts broken away to reveal the arrangement of the novel clearer in conjunction with the top roll of a roll stand such as used in textile processing equipment; and

FIG 2 is a cross-sectional view taken on line 22 of FIG. 1 showing the relationship of the illustrated components, and the passage of foreign material cleared from the top roll; and

FIG. 3 is a cross-sectional view similar to FIG. 2 showing another embodiment of the inventive concept with a modified support for the clearer tube.

Referring now moer particularly to the drawings, like numerals in the various figures will be employed to designate like parts.

As seen in FIGS. 1 and 2, the clearer 10 embodying the instant inventive concept comprises an elongate flexible walled tube 11 which may be formed of any one of a large variety of materials lending themselves to fabrication into an elongate tu-be structure as illustrated. Natural rubber or synthetic rubber compounds such for example as those in the Buna-N group are found particularly suitable. Tube 11 is formed with flap 12 which extends from the outer surface of the tube 11 and may either be molded integrally therewith, or secured thereto after formation of the tube. Flap 12 is preferably formed of a flexible material of the type of which the tube is formed, and extends tangentially from the tube surface as illustrated. Where the flap 12 is secured to tube 11 after tube formation a fillet 13 is formed between the flap and tube to provide desired smoothness of contour.

A support assembly 15 is provided for the clearer tube 11. Assembly 15 comprises a U-shaped bracket 14 having downwardly extending legs 16. Extending between the legs 16 of bracket 14 is a rod 17 which is secured at opposite ends thereof to the leg 16 by means of appropriate fastening members such as rivets, or preferably machine screws 18 as illustrated. Support rod 17 in the FIG. 1 and 2 embodiment of the invention is a hollow tube, preferably formed of aluminum or the like non-ferrous material. It may obviously be made solid without departing from the scope of the invention. The external diameter of rod 17 is less than the internal diameter of tube 11. As a result of this dimensioning, the clearer tube 11 is free to rotate about support rod 17. The base of bracket 14 is formed with a plurality of spaced slots 23 dimensioned to accommodate a fastening member such as machine screws 24. Slots 23 are of a length such as to permit transverse movement of the bracket with respect to machine screws 24.

A suction tube 30 of the Pneumafil type having a plurality of spaced inlet orifices 31 is provided for arrangement at a spaced distance from the clearer 10, as illustrated.

The clearer assembly 10 is shown as arranged for use in conjunction with the top crush roll of a Crosrol-Varga equipped card. The top crush roll 35 is provided with a spring-steel doctor blade 36 arranged to scrape the surface of the top crush roll 35 to keep the surface of the roll clear. The card in connection with which clearer is employed, is provided with crush rolls with a doffer cover flap 40 as shown in FIG. 2 hinged to the card housing.

In the embodiment of the invention shown in FIG. 3, the components identical to those in FIGS. 1 and 2 are similarly numbered. The modified components are the clearer support rod 17-3, which in this embodiment is solid; and the bracket 3 is formed with a flange 45 extending to a point adjacent clearer tube 11.

Operation The aforedescribed clearer assembly 10 may be used in a variety of situations where it is desired to clear a moving surface of foreign material. In the illustrated embodiment of the invention, the novel clearer 10 has been shown as used in connection with a top crush roll of the Crosrol- Varga equipped card.

Where so used, the clearer assembly 10 is affixed to the doffer cover flap 40 which is hinged to the card housing, as best seen in FIG. 2. The bracket 14 is affixed to the doffer cover 40 by means of screws 24 at a point such that the clearer tube 11 will contact the surface of top crush roll 35, with the clearer tube 11 resting under the action of gravity in frictional engagement with the surface of crush roll 35 so that the rotation of the crush roll will effect rotation of the clearer tube 11 as a result of the frictional engagement therebetween. The slots 23 in the base of bracket 14 permit adjustment of positioning of the clearer tube 11 from a point in contact with the top crush roll 35 just adjacent, or slightly overlapping the doctor blade 36 (to the left in FIG. 2), to a point relatively remote from the doctor blade 36 (to the right in FIG. 2) but still contacting the crush roll 35. Due to the fact that when the clearer tube 11 contacts the doctor blade, the rotation of the tube 11 causes it to ride up on the doctor blade which imparts frictional resistance to the rotation of the clearer tube as a result of its contact with the doctor blade 36. On the other hand when the clearer tube is moved to the right as viewed in FIG. 2, there is no ride-up of the tube on the doctor blade 36, and no frictional resistance offered by the doctor blade to the rotation of the clearer tube. As a result there is a greater speed in the right-hand position as viewed in FIG. 2.

In use, the bracket 14 is positioned so as to provide the slowest speed of rotation for the clearer tube 11, without danger of stopping, and with the tube 11, and its associated flap 12 striking as close as possible to thepoint of contact between the leading edge of doctor blade 36 and the crush roll 35.

As the clearer tube 11 is rotated as a result of its frictional contact with crush roll 35, flap 12 periodically contacts crush roll 35 and displaces the clearer tube from its pressure applying relationship with respect to the crush roll 35. It will be appreciated by those skilled in the art that the pressure applying relationship between the clearer tube 11, and the crush roll 35 serves to compact any foreign matter against the crush roll surface to thereby implement displacement of the foreign matter from the crush roll surface by the doctor blade. As a result of the periodic displacement of the clearer tube 11 from its contact with respect to the crush roll 35, the compacted mass on the crush roll surface will expand slightly, and this expansion is given further impetus as a result of the flap 12 which contacts the mass of matter, and kicks it up from the doctor blade and the crush roll into the airstream set up by the Pneumafil suction duct 30.

The action of the flap 12 additionally aids to disturb any equilibrium condition which may arise were the the clearer tube to remain in constant contact with the crush roll surface which might tend to promote the accumulation of foreign matter between the doctor blade and the crush roll with ultimate formation of a tail between the crush roll and doctor blade, and possible dropping of the accumulated foreign matter onto the processed web.

When access is required to the doctor blade, or crush roll for maintenance purposes, lifting of the hinged doffer flap 40 raises the clearer tube 11 from the doctor blade and crush roll and exposes same for any desired maintenance or other purpose.

In the FIG. 3 embodiment, the bracket flange 45 serves the twofold function of braking the rotation of the clearer tube 11 and cleaning same.

It is thus seen that a simple clearer has been provided having particular utility in connection With the crush rolls of a card, and which may be readily positioned in operative relationship with respect to the card components without interfering with desired carding operations.

The above disclosure has been given by Way of illustration and elucidation, and not by way of limitation, and it is desired to protect all embodiments of the herein disclosed inventive concept within the scope of the appended claims.

We claim:

1. In combination with a moving surface and an adjacent stationary surface, means for clearing foreign matter from said moving surface and said adjacent stationary surface, said means comprising: surface contacting means movably positioned adjacent said moving surface for movement thereby as a result of contact therewith; wiping means on said contacting means periodically displacing said contacting means from said moving surface as a result of the movement of said contacting mean and wiping foreign matter from the surfaces to be cleared; support means for said surface contacting means, said stationary support means frictionally engaging the interior of the surface contacting means to resist the movement of the surface contacting means imparted to said contacting means as a result of its contact with said moving surface to insure relative movement between said surface contacting means and said moving surface.

2. Means as in claim 1 in which said wiping means flex against the moving surface, whereby foreign matter will be kicked from the moving surface and the stationary surface as the wiping means moves away from the moving surface.

3. A clearer for removing foreign matter from a moving surface and an adjacent surface to be cleared, said clearer comprising: an elongate tube arranged in proximity to the moving surface; a stationary support for said tube extending through the interior of said tube and frictionally engaging the interior of said tube while permitting rotation of the tube in response to the movement of the moving surface, movement of said tube markedly retarded by the frictional engagement of said support to provide relative movement between said tube and the moving surface; and a flap on said tube extending therefrom into abutment with the moving surface and adjacent surface to be cleared.

4. A clearer as in claim 3 in which said support com prises: a rod extending through said tube, said rod having an external diameter less than the internal diameter of said tube, and mounting said tube for rotation with respect to said rod.

5. A clearer as in claim 4 in which said support comprises: a U-shaped bracket having downwardly extending legs, and said rod extends between said legs through said tu e.

6. A clearer as in claim 3 in which said flap is flexible, whereby the free end of the flap kicks foreign matter from the moving surface as the flap moves out of contact with the surface.

7. In a textile card having a top crush roll, and a hinged cover member arranged over said top crush roll; a doctor blade arranged for scraping contact with respect to the crush roll; a clearer for removing foreign material scraped from the crush roll by said doctor blade, said clearer comprising: an elongate clearer tube arranged in contact with the surface of the crush roll; a stationary support rod extending through said tube and supporting same for marked frictionally retarded free rotation as a result of its contact with the crush roll; a bracket supporting said support rod, said bracket adapted for adjustable positioning with respect to said cover member to permit variation of positioning of said clearer tube from a point overlapping said doctor blade to a point remote therefrom, while maintaining said clearer tube in contact with said crush roll; and a Wiping flap on said tube extending from said tube into contact with said crush roll and said doctor blade as the tube is rotated.

8. Apparatus as in claim 7 in which a suction tube is arranged in proximity to said doctor blade.

9. Apparatus as in claim 7 in which said flap and said tube are formed of a flexible material.

10. Apparatus as in claim 7 in which said bracket is provided with a flange extending to a point contacting the surface of said clearer tube, whereby foreign matter on the surface of the clearer tube may be dislodged, and the rotation of the clearer tube is braked.

References Cited UNITED STATES PATENTS MERVIN STEIN, Primary Examiner.

DORSEY NEWTON, Examiner. 

1. IN COMBINATION WITH A MOVING SURFACE AND AN ADJACENT STATIONARY SURFACE, MEANS FOR CLEARING FOREIGN MATTER FROM SAID MOVING SURFACE AND SAID ADJACENT STATIONARY SURFACE, SAID MEANS COMPRISING: SURFACE CONTACTING MEANS MOVABLY POSITIONED ADJACENT SAID MOVING SURFACE FOR MOVEMENT THEREBY AS A RESULT THEREWITH; WIPING MEANS ON SAID CONTACTING MEANS PERIODICALLY DISPLACING SAID CONTACTING MEANS FROM SAID MOVING SURFACE AS A RESULT OF THE MOVEMENT OF SAID CONTACTING MEANS AND WIPING FOREIGN MATTER FROM THE SURFACES TO BE CLEARED; SUPPORT MEANS FOR SAID SURFACE CONTACTING MEANS, SAID STATIONARY SUPPORT MEANS FRICTIONALLY ENGAGING THE INTERIOR OF THE SURFACE CONTACTING MEANS TO RESIST THE MOVEMENT OF THE SURFACE CONTACTING MEANS IMPARTED TO SAID CONTACTING MEANS AS A RESULT OF ITS CONTACT WITH SAID MOVING SURFACE TO INSURE RELATIVE MOVEMENT BETWEEN SAID SURFACE CONTACTING MEANS AND SAID MOVING SURFACE. 